The city of Kawasaki in Japan holds an annual Halloween costume parade. More than 100,000 watch it and 2,500 people take part.
The Americanised (Americanized?) Halloween that we experience today actually originated in the Celtic fringes of Britain, and was adapted over the decades by Christian traditions, immigrants conventions and an insatiable desire for sweets.
Like the Celts, the Europeans of that time also believed that the spirits of the dead would visit the earth on Halloween. They worried that evil spirits would cause problems or hurt them. So on that night people wore costumes that looked like ghosts or other evil creatures. They thought if they dressed like that, the spirits would think they were also dead and not harm them.